Fluid-operated change-speed gear



June 17 '1924.

' lH. SCHNEIDER FLUID OPERATED CHANGE SPEED amm Filed sem. 1o. 192s 2 shuts-sheet z of rotation may be obtainedenclosing. said two-rotors. and veccentrically arrangedto the outerl rotor, and meansto' A tiallyl lower than with known. gears. 35.

rLUm-ormrnn CHANGE-SPEED om Application mea'seppember 1o, 192s. semi No; salam..

To all whom t may comem:

Be it known that I, HErNRIcH SCHNEIDER, a citizen of the Republic of Switzerland, residing at Illnau, Canton Zurich, Switzerland, have invented certain new and useful Improvements in Fluid-Gperated Change-v Sp'ed Gears, of which the 'following is a speciication, reference being had therein to the accompanying drawing.

The present invention relates to fluid 'operated change speed gears of the type in which any desirable .speed ratio between a maximum speed andnzero in4 both directions The .change speed gear accordin nels for directly connectingwith'each other .the workingspaces of the rotors, a casing alter one of -said -eccentricitiesn The changespeed.

present' invention di ers from the known gears inasmuch asthere are, no stationary' maclnnery parts such as guide apparatus o'r controlling or -ns'arranged between the the two rotors are-directly connected to each other. v In. consequence thereoflthe connectingchannels are shorter-and the losses by friction, leakage and throttling are substaneiliciency'of lthe gears according to the present. invention is 'thereforeveryliigh.l y

Constructional x .examples of the. subject matter-lof the present invention' are'illustrated on 4 the accompanying i drawings inwhi'chz'v i Figs. 1-3 show in a diagrammatic' manner'A the two 'rotar pumps of a gear, Athe change of speed van the. reversing of the direction ofrotation 'beineefectedby'- an alterathe casing of-'the `gear .the relative position- Fig-.iisso that both' tion ofthe :position relatively tothe rotors of the parts shown ,in

rotors rotate in the'sal'ne direction, Fig. 2 shows .the position' in whichlthe gear.- is inoperative 'and in the lposition,illustrated in Fig'. .-3 the-.rotors rotate in 'directions that.-

-are-opposite'to each other.

A Fig. 4 lshows in a vertical longitudinal sec.

to thepresent invention comprises in .com ination two rotors 'of the rotary vane type one ar.v ranged eccentrically within the other, chan' 'ear according to. the

The.

vmanner known with rotary pumps.

- tion, a first 'constructional example of a 'second constructional example and Fig. 9- is asection along line IX-IX of Fig. 8. f a

` he rotors Iand 42 arerovided with Avanes 4 and 5 respectively a apted to slide and eccentrically to the latter. The working .spaces 20 and 22 of the rotor '1 are in d1- 4rect. connection with the working spaces 21 and .of the rotor 2 by the-channels 7.

- in radial slots 11 and 13 respectively. The

The slotsfll ofthe rotorl are connected to the. working spaces of the rotor 2 by vmeans of bores 12; grooves 14 are provided in connection with theradial slots 13 of the rotor 2 so that the-slots 'are always filled with Vthe working fluid.

4Grooves 25 and 26V respectively are provided on the parts ofthe inner surface of two rotors andt atthework1ngspaces of .3o

the'casingv 3 that correspond to the suction tive spaces may take' place.

'Ihe'above -described change speed gear i works-ias follows:

. When the rotor 1` in Fig. 1 is rotated in creased-in the working spaces 20 in ge e fluid {iows throughtlie bores -7 into Athe working spaces 21of the rotor 2 and causes arrow l'the pressure ofA the fluid is inrection as indicated by the arrow in Fig. 1.- Inl the working spaces 22 of the rotor la suction-pressure is generated so that the driving Huid flows vfrom. the .spaces 23 of the .rotor 2 into the spaces 22 of the rotor 1.

Fig. 2 shows the gear inwhich by a displacement of the casing 3 in the upward direction .and relatively to the rotors the work- ,the-"clockwise direction as indicated'by the the latter t0 turn also inthe clockwise di- 26 is rotatabl eccentrical 58 are connected .10 and thereby a flow of the fluid through the channels 7 into the spaces 23, whilst the fluid returns from the spaces 21 to the-spaces,

20,'so that a rotation'of the rotor 2 i n the anti-clockwise direction is caused, as 1s 1n- 16 dicated by the arrow C in Fig. 3.

Referringinow to the constructional e'xample illustrated in Figs. 4-7, 31 de notes the driving shaft which drives the inner rotor 40 by means of the gear wheels 32 20 and 33, the rotor 40 being rotatably mounted in rollel` bearings and 36 and provided with radial slots 41 inA which the vanes 42 are adapted to slide. The inner rotor is surrou'ndedby the outer rotor 50 which mounted in the casing 37l and to the rotor 40"-by means of tlie roller arin and 46. The Jouter rotor is- 'provided Withradial slots 51 in Vwhichthe vanes 52 are adapted to slide.

30 Channels 55 are arran ed in the rotor 50 throu hywhich the wor ing ll'uid mayv flow to and fro between the rotors. In the; c asing 37 which encloses both rotors equalizing .channels 57 and 58 are arranged by which 35 all the workings aces` of both rotors in which pressure an suction res ectively is generated are interconnected. T e vanes 42 are guided in a concentric groove 44 provided in. the rotor 50 and the vanes 52 are 40 guided in a concentricgroove 54 in the casmg 37. The rotor 50 is further provided with a toothed rim`53 which is in mesh with a gear wheel 56fixed to the driven shaft 60.

A f gear wheel ump 63 driven by the 45 gear wheels 32 an 62 serves .for filling the 'change speed geanwith Workin fluid andfor replenishing the lluid lost The um 63 sucks the lluid from the casin 37) and)` forces it through a delivery chan- 65.- This channel is connected to the v"casing on both sides of Vtherotors by means of lateral passages 65 and 65". Two pressure actuated valves 70 andv 70 connected by a single valve-stem '70 control these passa esrso thatwhenone valve as 70 is jclose bythe pressure on one side of the gear, the other valve as 70 is automatically opened by the movement vofthe -first named valve and automatically establishes a con-- 60.k nection to the ,actual suction side of the gear.' The two equalizing channels 57 and valve 181.

The rotor 40 is mounted by means of the'roller bearings 35 and 36 in two rockchannels 55.

y leakage. i

y channelsito a safetying levers 71 and 72, turnabl arranged about fulcrum pins 74 and 75 xed in the casing 37. The levers 71 and 72 are linked b means of tie-rods 76 and 77 to eccentric pins 78 and 79 of a shaft 80, so that a turn- 1ng of the shaft 80 by manipulating the hand lever 7 3vcauses an alteration of the eccentricity of the rotor 40 with regard to the rotor 50 and the casing 37.

In accordance with the position of the rotor 40 the latter unips working fluid to one or the other si e through the channels 55 into the working spaces of the rotor 50 and causes a turning motion of the latter in the one or the other direction, whilst `the rotor 40 sucks the working fluid from the other side of the rotor 50 through the When the eccentricity of the rotor 40 with regard to the rotor 50 is made equal to zero no pressure or delivery of the Working fluid is caused, and the change speed gear runs idle. With the maximum positive eccentricity between the two rotors the rotor 50 rotates ahead Iwith the greatest speed, with the maximum negative eccentricity the rotor 50 rotates astern with the greatest speed and any intermediate speeds may be obtained by adjusting the eccentricity between the said maximum positive and the maximum negative amounts.

In the second constructional example illustrated in Figs. 8 and 9 the inner rotor 110 is directly connected to the driven shaft 101 and is rotatably mounted in the casing 170 by means of. the roller bearin 105 and 106. The rotor 110 is provide with radial slots 111 and vanes 112 slidable in the former and' is surrounded by the outer rotor 120 having slots 121 and vanes 122. The outer rotor 120 is rotatably mounted in the casing 170 in an eccentric position to the rotor by means of the roller bearings and' 116. Channels 125 for connecting the working spaces of the two rotors `and equalizing channels 127 and 128, are

provided as in the first coustructional example, the guide facings 114 and 117 in Whichthe vanes 112 and 122 are laterally guided in order to effect their sliding movemente in the radialdirection are eccentrically arranged to the respective rotors. The rotation of the rotor is derived from the driving shaft 130 through the interpositionl of'the gear wheels 123 and 126. A gear-wheel pump 133 is further provided which delivers working fluid through a channel 135 and an automatic double seat valve into the gear. Both rotors are enclosed in the casing 107 which is adapted to be displaced relatively to the rotors in order to alter the speed ratio between. the

driving and the driven shaft. To this end the casing 107 is provided with pin-shaped extensions 141 and 142 which are guided in bores provided in the outer casing spaces on opposite sides o iluid delivery channel'having lateral passages` v gnam that the casing 107 is lifted or lowered by means of handlever 143, eccentric shaft 150 and link 146. Safety valves 151 are provided for preventing an excessive pressure 4rise within the gear. l

The above described change s eed gearis particularly well adapted for riving machine tools and lifting mechanisms of the various types; it requires little space, it is of a simple design and any s d within a wide range can be obtained bfea simple adjustment of a hand-lever. v 1

I claim: l 1. In a 'luid operated changespeed gear, two eccentrically arranged rotors, a casing surrounding the rotors and eccentric to the outer rotor, said rotors andcasing forming eccentric suction and pressure working spaces on opposite sides of the rotors and casing, channels in the outer rotor connect# ing the working spaces ofthe rotors, a fluid delivery channel adapted to communicate with the casing on opposite sides of the rotors, means for transferringthe, working fluid from the casing-to the channel, means in the latter operable by pressure on the pressure side of the rotors for' establishing communication between the channel and the Gsuction side of the casing, and channels in the casing for equalizing the pressure in the working spaces.

2. In a fluid operated change speed gear, two eccentrically arranged rotors, a casing "surrounding the rotors and eccentric tothe outer rotor, said rotors -and casing forming eccentric suction and ressure working i) the rotors, means to vary the relative eccentricity of the rotors and casing, channels inthe outer rotor connecting the working spaces of the rotors, a uid delivery channel adapted to communicate with the casing on opposite sides of therotors, means for pumping the workin iuid from the casing'to the channel, an

valvesoperable by the ressure on the pressure side of the rotors or establishing communication between the channel andthe suction side of the casing. Y D 3. In a fluid operated change speed gear, two eccentrically arranged rotors, a casing surrounding the rotors, and eccentricfto the outer rotor, said rotors and casing forming eccentric suction and pressure working spaces on opposite sides ofthe rotors, `means to vary therelative eccentricityfof the rotors and casing, channels in the outer rotor con.

necting the` working spaces bf the rotors,'a

adapted to communicate with the casing on opposite sides of the rotor, and valves controlling the lateral passages and ada ted to simultaneously close one passage an o en the other, whereby the channel is lace in communication with 4the suction si e of the rotors. y l t 4. In a Huid operated change speed gear, two eccentrically arranged rotors, a casing surrounding the rotors and eccentric to the outer rotor, said rotors andcasing forming eccentric suction and' pressure working spaces on opposite sides o the rotors, means to vary the relative eccentricity of the rotors l and casing, ychannels in the' outer rotor connecting the working spaces of the rotors, a luiddelivery channel', a ump for transferringA theworkig fluid .om the casing to the channel, pu1np-.,operating mechanism actuated by one of the rotors, passages connecting the channel with the casing on oppor site sides of the rotor, a valvevopcrable by pressure in the casing to close one of the passages, and a valve operable by the movement of the aforesaid valve to open the other ,passage whereby the channel is placed in communication with the suction side of the` rotor. f

5.l In a Huid operated change speed gear, 'two'eccent'rically arranged rotors, a casing surrounding the rotors and eccentric to the outer rotor,l saidrotors and casing forming eccentric suction and pressure working'l spaces on opposite sides of the rotors, channels in the outer rotor connecting the working spaces of the rotors, channels in the casing for.. equalizin the pressure in the working spaces, an safety valves connected withfthe equalizing channels for preventing excessive pressure in the,y casing, a driving shaft operatively connected to one vof the rotors, .a driven shaft operatively connected to the other rotor, a -iuid delivery channel communicating with the casin a pump operativelyconnected with one o the rotors for transferring working fluid from the casing to the. channel, laterally arranged passages communicating with the channel and.

vconnected with the casing on opposite sides i of the rotor, and valveswcontrolllng the laterally arranged passages operable by pressure in the casing to simultaneously close one passage and open the'other, whereby lworking luid is supplied to the suction ,side of the rotors.

In testimony whereof I azr4 HEINRICH scninrnnn, 

